Digging in the dirt: Getting to know the Dimetrodon of the Texas Permian Red Beds

I love my job. Not everyone can say that. My avocation and vocation are as two eyes with one sight (paraphrasing Robert Frost). Part of that job was taking a group of 15 patrons up to the Museum’s dig site outside Seymour, Texas. There, under the tutelage of Dr. Robert Bakker and David Temple, the group learned how to properly excavate bones of ancient animals —  in this case, Permian synapsids, amphibians, and fish.   

I got to go through a spoil pile (the pile of debris and castoff that others have thrown aside), and found several bits of our very early ancestors, the synapsid Dimetrodon.  I also worked on removing the overburden (the rock and dirt that is over a site we want to excavate), and found bits from a dorsal spine of a Xenacanthus, an ancient shark. It was the fulfillment of a childhood dream (as I child I played paleontologist rather than fireman and my first Deinonychus is still buried out back at my childhood home).

But I’m not the only one who dreamed of finding fossils in Texas.

Noted Swiss naturalist Jacob Boll came to Texas in 1869 to join La Reunion commune that is located in the current Reunion District of Dallas. (The Reunion Tower is named in honor of that small settlement.) La Reunion commune was responsible for the first brewery and butcher shop in the Dallas area. It also helped Dallas become the center for carriage and harness making.

Jacob Boll came over to set up high schools based in scientific inquiry. Through the late 1870s, he searched for fossils for Edward Drinker Cope, the noted “Bone Wars” paleontologist. Boll found over 30 new vertebrate species from the Permian period, which can be seen in the collections of the American Museum of Natural History.  Unfortunately, on his last trip, he was bitten by a rattlesnake, wrote some final letters to his family, composed a short poem in German, and died.  

In the Permian period, Texas was very different from today. Near Seymour, there were rivers and seasonal flood plains. However, even with this picture, there are still unexplained factors about the life of Dimetrodon — one being that there was not enough prey to sustain the population that we have found in the fossil record. While the Dimetrodon were making sushi out of Xenacanthus and chewing on some Trimerorhachis legs (like frog legs, only much shorter), there was not enough food to go around.

Now add to this case the curious fact that almost no Dimetrodon skeleton found has an intact tail. Anyone who has been to a good Cajun restaurant will know that the best meat on an alligator is the tail. And Dimetrodon would agree — hence the lack of tails.

But even this does not account for all the food necessary to keep all the predators alive.  Where is the missing food?

Dr. Bakker gave us a couple of hints as to what he thinks is the answer. 

 A few miles away from the site, there is an old Permian river basin where we find Edaphosaurus, a large Dimetrodon-like herbivore. Was it possible for Dimetrodon to walk a few miles, ambush an animal about its size, then walk back for a rest? This would provide food for the population.          

If you are interested in learning more about the Texas Red Beds, join us for our Fossil Recovery Class on May 20. You can go through some of our collection from the trip and learn about fossil collecting and identification techniques.

Click here for more information.  

Paleo-powered pictures for everyone on Sept. 24: Bakker’s back with a big book of dinosaurs

Our esteemed curator of paleontology, Dr. Robert T. Bakker, is back in town and on campus at HMNS Tuesday, Sept. 24 for a very special book signing and lecture.

Coinciding with the release of his brand new picture book, The Big Golden Book of Dinosaurs, Dr. Bakker will lead a lecture in the Giant Screen Theatre, to be followed by a book-signing session at the Museum Store.

From the Google

Among the topics to be addressed during the lecture with Dr. Bakker’s inimitable enthusiasm are: Was T. rex a slow-footed stumble-bum? (No!) Were tyrannosaurs devoid of any gentle, nurturing gestures? (No way!) Were gigantic meat-eating dinos ticklish? (You bet!) Could you out-run an angry charging triceratopsine? (Don’t even try.)

Kid-friendly dino activities will be available throughout the Grand Hall prior to the lecture, beginning at 5 p.m. For more information or to book your tickets in advance, click here!

Black Hills Institute

Today’s post is by Sami Mesarwi, a member of the Museum’s marketing staff who recently traveled to South Dakota to visit the Black Hills Institute. 

If the company you work for had to send you on a business trip anywhere you wanted to go, where would it be?  Paris?  London?  Shanghai?  How about Hill City, South Dakota?  Probably wouldn’t be a first choice for too many out there… And while I would have said the same before my trip to the Black Hills Institute of Geologic Research (and I probably still wouldn’t be able to pass on Paris), this paleontological-Mecca should definitely be in the running for you dino-die-hards out there.

Black Hills Institute Outside Facade
The Black Hills Institute of Geological Research

I’ve always loved dinosaurs. 

In fact, Michael Crichton’s Jurassic Park is still one of my all-time favorite books (I may have grown up thinking that Crichton’s logic used in the novel to try and resurrect dinosaurs using the DNA found in preserved mosquitoes, as well as amphibians to fill in the holes, was flawless, but I’ve come a long way since then).  So, going on this trip seemed like it was going to be quite enjoyable from the start.  Our mission was simple enough: to go up and get some photos of the fossils that will eventually be on display in the museum’s upcoming new paleontology hall, opening summer 2012.

A coworker and I took the trip up to South Dakota in April, a time when Houston weather had consistently already warmed up to 90+ degrees outside.  However, surprising to all of us on the trip, we were greeted by snow in South Dakota!  Even though it was April, it was a Winter Wonderland—the color of the snow that covered the ground literally blended in with the sky’s horizon. Needless to say, it was pretty cold.  But I was able to get some pretty nice still shots out of it.

Winter Wonderland
Winter Wonderland!

Day one of our trip to South Dakota was a whirlwind of sights and sounds from within the Black Hills Institute. 

Everyone met up inside the Institute with the famed Peter Larson, the Yoda (though not quite as old) of casting fossils and of T. rex.  He gave us a brief history of his background and of the Institute while in the main lobby area, a who’s who of dinosaurs from several different eras.  In addition to the infamous SUE the T. rex, there were examples of Triceratops, Struthiomimus, Acrocanthosaurus, what seemed like an infinite amount of ammonites, and so much more, all filling an area about the size of an average backyard in the suburbs.  It was amazing—I’ve never seen so many dinosaurs in a compact area before.

Pete Larson
Pete Larson in the zone.
Dino Showroom
The Black Hills Institute Showroom

Onwards we continued to the prepping areas (a separate building from the museum itself), showcasing a few dinosaurs in the development and mounting stages. Pete told us about several of the specimens we’d be getting here at HMNS, before all of the paleontologists on hand broke into a discussion about the immaculate condition some of the fossils were in (I can’t give away too much about what in particular we’re getting—you’ll just have to wait and see!).  Before this trip, I thought I could hold my ground pretty decently well in matters of dino-speak.  But boy was I wrong.  Being surrounded by so many accomplished and literally world-renowned paleontologists (including Pete Larson, Dr. Robert Bakker, and so many others) was really very exciting.  But also quite humbling.

Pete then took us to the casting/molding area, where several Black Hills employees were diligently working to create some very impressive casts of fossils that they had.  They poured the liquid silicone rubber into the two mold halves, and, with some of the smaller ones, fastened them together with—interestingly enough—Legos! Turns out those colorful, little building blocks aren’t just fun to play with, but are also way more practical than you would think…

Pete Larson Bob Bakker
Pete Larson and Dr. Bob Bakker examining a recent find.

Our second (and final) day of the trip allowed for us to talk up close with Pete himself. 

Pete told us all about the Black Hills Institute itself and how it came to be—in 1974, as an earth science supply house, providing teaching specimens for colleges and universities, before branching out into doing museum exhibits.  In fact, as Pete points out, the products coming out of the Black Hills Institute can be found on every continent in the world (though he was mindful to exclude Antarctica from the list—hardly as impressive now, if you ask me).  After he answered our countless questions, Pete allowed for us to roam around the Black Hills Institute at our leisure, getting some shots of whatever it is that we wanted.  We took still shots of some of the specimens that will be making an appearance in the new paleontology hall, as well as some of the stars of the show.

After that, we grabbed a quick lunch at the corner bistro before heading back home to Houston.  Though we did make a quick stop on the way back… As we were only about 15 miles away from Mount Rushmore, we went ahead and visited the famed monument on our way to the airport. Quite breathtaking, I must say!  To me, the tranquility of the park where the monument is located, coupled with the remarkable stature of the presidents whose faces are forever immortalized in the mountain’s façade, were equally as impressive to me as the mountain goat we saw.

Mt. Rushmore
Mount Rushmore.

All in all, the trip to Hill City, South Dakota was so much cooler (both, literally and figuratively) than I originally anticipated.  While the city itself isn’t exactly the largest out there (population: 948), or the most exotic of your travel destinations, it should absolutely be a front-runner for all of you dino-enthusiasts out there.

Discovery! Mass Burial of Ancient Red Beds Amphibians Uncovered

PhD scientists aren’t the only ones to make spectacular new fossil finds. Case in point: a skilled bulldozer operator digging a cattle tank in Baylor County caught a glimpse of fossils – hundreds of tree trunks, branches, leaves and…skulls! It’s the biggest discovery ever of flat-headed, bottom-living frog-relatives in the famous Clear Fork beds.

Background of Discovery – the “Age of Frog-oids”

The north Texas Red Beds from the Early Permian Period are most famous for the fin-back reptile Dimetrodon, a tiger-sized predator who was close to the direct ancestry of furry mammals, including us. But the Red Beds habitats swarmed with amphibians too, creatures who hatched from frog-like eggs and breathed with gills early in life the way salamanders do today. So common and diverse were Red Beds amphibians that this geological time-zone can be called: “The Age of Frog-oids.”

Some frog-oids were huge and armed with alligator-shaped skulls. Some were tiny and squirmed through the mud like squatty snakes. Others ruled the pond bottoms and stream beds, hugging the mud with low, wide bodies and wide, flat jaws – a design ideal for ambushing crustaceans and fish passing overhead. One of the dominant bottom-huggers was the “Panzer Mudpuppy,” a twenty-pound amphibian with powerful jaws, curved fangs, and big eyes that scanned the water above. Known technically as Trimerorhachis (“Three-Part-Spine”, in honor of the vertebrae, which were composed of three sections), this flat-bodied hunter was an extraordinary geological success. It survived for twenty or thirty million years, a constant companion to the big Dimetrodons who prowled on shore.

The “Panzer” part of the nickname comes from the armored skin. Amphibians today have mostly naked, frog-oid/toad-oid skin. Red Beds amphibians were different. Their bodies usually were completely covered with thin bone scales that worked like the scale-armor suits of medieval warriors. Darwinian theorists have suspected that “Panzer Mudpuppies” were key elements in the Dimetrodon diet. Few land herbivores were available, so the fin-back predators may well have waded into the water to snag amphibians. If the theory is true, then Trimerorohachis played a vital role in the survival of our reptilian ancestors.

Gaps in the geological record

Despite 130 years of intensive study, “Panzer-Mudpuppy” history still had gaps. This amphibian was very common in the earlier Red Beds, like those in Archer County. But then it became rare. In the later Red Beds, the Clear Fork Group, good skulls and bodies are few and far between. What happened? Were there local habitats where “Panzer Mudpuppies” enjoyed reproducing and growing in Clear Fork time? No one knew, until Jimmy Smajstrla and his bulldozer arrived at the Craddock Ranch. Thanks to the generosity of Mr. Bill Whitley, ranch owner, the Houston Museum has been surveying all the fossil sites in the Clear Fork sediments that outcrop in the ranch. Bits and pieces of “Panzer Mudpuppies” were recovered but no specimen had a complete skull or jaws.

The Discovery

Mr. Smajstrla had a ranch job to perform: excavate a new tank to trap water for the cattle. However, he also had a talent for paleontological discovery. When his twenty-year-old Caterpillar, named “YSOB,” was digging down to the ten foot depth, the blade overturned grey clay chock full of fossilized plant parts. Smajstrla salvaged many valuable chunks and led the HMNS party to the spot. Fossil wood is rare in the Clear Fork, so the discovery was exciting.

Then came what no digger had dared to hope for. Even deeper went the ‘dozer. Fossil parts were in the bed below the plants. Not botanical remains this time, but what thrills the heart of every paleontologist: skulls and jaws, dozens and dozens of them, many perfect. For the very first time, science had a beautiful sample of later “Panzer Mudpuppies.” Some of the heads were larger than any previous discoveries. The official name of the skull-bed is “The Judy Site,” in honor of Mrs. Judy Whitley. What will the “Judy Site” tell us? Lots. We’ll know much more about the habitat choice of the “Panzer Mudpuppies.” And we’ll be able to detect micro-evolutionary changes. Investigations have just begun.

We look forward to sharing updates on our investigations as well as new finds with you. Stay tuned!